The development of stable compositions for suppressing dust on road surfaces, dirt, and the like, has been problematic. Numerous dust-suppressing compositions for road surfaces have been developed. However, very few remain stable (less than 1% separation) for long periods of time because the chosen ingredients cannot properly homogenize, thus requiring expensive reconditioning and mixing between applications when the product has been dormant for a short period of time. Further, few dust suppressant compositions effectively suppress dust and at the same time soak into the soil. Many road dust compositions containing tar and other asphalt compositions fail to absorb into the soil adequately, forming a coating on the surface of the soil. This coating easily erodes upon exposure to weather conditions. Others leave the soil surface tacky, permitting the dust suppressant to adhere to shoes and tires. The surfaces of automobiles traveling on roads which have had such compositions applied to it inevitably become flaked with a combination of soil and tar, a substance difficult to remove. Further, the dust suppressant must be reapplied frequently as it comes off the surface of the road and onto traveling vehicles. Still others require extensive curing times which extend the time during which the public is prevented from accessing the road for travel.
U.S. Pat. No. 4,801,635 to Zinkan et al. discloses a composition for coal dust suppression which comprises a mixture of water, a water-soluble anionic acrylic polymer, a non-ionic polymer, a non-ionic surfactant, and an anionic surfactant. There is no disclosure that this composition is suitable for use as a road dust suppressant and it is unlikely this composition would effectively soak into soil to prevent soil surface tackiness.
U.S. Pat. No. 4,561,905 to Kittle discloses a composition for suppressing coal dust. The composition contains an asphalt and oil emulsion mixed with non-ionic and cationic surfactants, a colloid and water. The mixture is aerated and applied in the form of a foam. After the water evaporates, a tacky film remains on the surface of the coal.
U.S. Pat. No. 4,001,033 to Anthone et al. discloses a road base stabilizer comprising a mixture of lignin sulfonate, a combination of dispersants, a fatty acid ester of polyglycerol, and polyoxyethylene ethers of alkyl-substituted phenols. The composition is mixed with pulverized soil to prepare a road base.
U.S. Pat. No. 4,571,116 to Patil et al. discloses a dust suppressant comprising a blend of asphalt, a colloid, and conventional surfactants. The Patil et al. patent discloses a variety of emulsifiers and colloids, but does not specifically disclose how to synergistically select and combine the most beneficial constituents.